principal

The educator who has executive authority for a school.

“she sent unruly pupils to see the principal”

The major party to a financial transaction at a stock exchange; buys and sells for his own account.

An actor who plays a principal role.

Capital as contrasted with the income derived from it.

(criminal law) any person involved in a criminal offense, regardless of whether the person profits from such involvement.

The original amount of a debt on which interest is calculated.

Most important element.

“the principal rivers of America”

“the principal example”